This page has 2 threads | Add post

Finding our videos useful? Please consider helping us to share more!

VBA - advanced videos | Excel VBA Part 20a - Application Events

Posted by Andrew Gould on 26 November 2015

Excel VBA Part 20a - Application Events

In an earlier video in the series we've seen how to write event-handlers for workbooks and worksheets; this video teaches you how to access events of the Excel application itself! You'll learn the significance of the WithEvents keyword, a couple of the basic application events such as the new workbook event, and how to use a basic class module to keep your application event handlers neatly organised.

See our full range of VBA training resources, or test your knowledge of VBA with one of our VBA skills assessment tests.

There are no files which go with this video.

There are no exercises for this video.

Making a video bigger

You can increase the size of your video to make it fill the screen like this:

Play your video (the icons shown won't appear until you do), then click on the full screen icon which appears as shown above.

When you've finished viewing a video in full screen mode, just press the Esc key to return to normal view.

Improving the quality of a video

To improve the quality of a video, first click on the Settings icon:

Make sure yoiu're playing your video so that the icons shown above appear, then click on this gear icon.

Choose to change the video quality:

Click as above to change your video quality.

The higher the number you choose, the better will be your video quality (but the slower the connection speed):

Don't choose the HD option shown unless your connection speed is fast enough to support it!

Is your Wise Owl speaking too slowly (or too quickly)? You can also use the Settings menu above to change your playback speed.

This page has 2 threads

Add a new post

From:	warmday
When:	22 Apr 20 at 11:15

Reply to warmday

I am trying to learn the mertis of creating your own events.

Can you please explain the use of the following code?

This is in Sheet1:

Option Explicit

    Dim WithEvents SomeClass As Class1

Private Sub SomeClass_ShowMessage(Message As String)

    MsgBox Message

End Sub

Private Sub Worksheet_Change(ByVal Target As Range)

    Set SomeClass = New Class1

    Call SomeClass.SomeMethod

End Sub

This is in Class1:

Option Explicit

Public Event ShowMessage(Message As String)

Sub SomeMethod()

RaiseEvent ShowMessage("Hi")

End Sub

My (limited!) understanding of this code is that when something changes on Sheet1, a messagebox displays the message "Hi".

But why go to all that length using a class module, as well as Raise Event, Event and WithEvents when you could simply write this in Sheet1:

Private Sub Worksheet_Change(ByVal Target As Range)

MsgBox "Hi!"

End Sub

Thanks

From:	Andrew G
When:	22 Apr 20 at 16:48

Reply to Andrew G

The short answer is that you wouldn't! The example you've given is one to demonstrate the basic principles of custom events. In reality you'd be writing custom events which are meaningful in the context of the class in which they're defined. A common, generic approach is to raise custom events both before and after something has happened in a class. What that something is will be entirely dependent on what you're designing your class to do.

http://cpearson.com/excel/Events.aspx - scroll to the end for a short section on custom events.

https://rubberduckvba.wordpress.com/2019/03/27/everything-you-ever-wanted-to-know-about-events/ - this contains a link to a Battleships game which uses lots of advanced VBA techniques

From:	warmday
When:	08 Feb 20 at 21:16

Reply to warmday

The following is code form your video:

' ThisWorkbook

Option Explicit

    Private xlApp As EventApp

Private Sub Workbook_Open()

Set xlApp = New EventApp

End Sub

' Class Module called EventApp

Option Explicit

Private WithEvents xlApp As Application

Private Sub Class_Initialize()

Set xlApp = Application

End Sub

Private Sub xlApp_NewWorkbook(ByVal Wb As Workbook)

    Wb.Worksheets("Sheet1").Range("A1").Value = "Created on " & Date
    Wb.Worksheets("Sheet1").Range("A2").Value = "Created by " & Environ("UserName")

End Sub

I have seen this from a book:

' Class Module called EventApp

Public WithEvents xlApp As Application

Private Sub xlApp_NewWorkbook(ByVal Wb As Workbook)

    Wb.Worksheets("Sheet1").Range("A1").Value = "Created on " & Date
    Wb.Worksheets("Sheet1").Range("A2").Value = "Created by " & Environ("UserName")

End Sub

' Standard Module

Public myAppEvent As New EventApp

Sub TrapAppEvent()

Set myAppEvent.xlApp = Application

End Sub

Both versions work but there are some differences.

1. Your variables are declared Private whereas the other version is declared Public, eg Private xlApp As EventApp / Private WithEvents xlApp As Application

The other version declares: Public WithEvents xlApp As Application / Public myAppEvent As New EventApp

2. The other version contains this line:

Set myAppEvent.xlApp = Application

but yours doesn't.

Can you please explain the significance of these two points.

Thanks

From:	Andrew G
When:	25 Feb 20 at 08:42

Reply to Andrew G

Hi there,

1. Variables declared as Private are accessible only within the module in which they are declared. Variables declared as Public can be referenced from any module in the same project. I declared xlApp as Private in both the class and normal modules so that the variable was specific to each module.

2. The same line appears in my code in the Initialize event of the class module - the Initialize event is triggered when a new instance of the class is created.

I hope that helps!

Add a new post

Book any course as classroom, onsite or online training, or as one-to-one consultancy

Free resources

Paid services

Getting help

Where we are

Where you are

Online

Transparent reviews

Delivery of courses

Nicer to work with

Reliable and established

Our training courses

C#

Excel

MySQL

Power Apps

Power Automate

Power BI and DAX

Python

Report Builder

SQL

SQL Server

VBA Macros

Other training resources

Blogs

Exercises

YouTube tutorials

YouTube shorts

Test your skills

Consultancy

Courseware

Self-paced courses

Newsletters

Publications

Our training venues

London

Manchester

Across the UK

At your site

Online

Why we are different

Hundreds of published reviews

Small class sizes

Outstanding courseware

Online classroom

(Almost) no cancellations

Wise Owl trainers only

Genuine integrity

Invoices after training

30+ years of Wise Owl

Our top 100 clients

BY CATEGORY

VBA CATEGORIES